Sliding doors are commonly used in commercial buildings, airports, and the like. Such sliding doors typically have one or more doors carried in a surrounding frame (e.g., made of metal or wood) adapted for sliding movement back and forth upon a track or a rail. These sliding doors provide convenient access for ingress and egress. For some applications it is desirable to secure these sliding doors with a lock to prevent unauthorized entry. In other applications, it is desirable to have sliding doors with sensors that determine if the doors are closed and locked and provide a warning signal if the doors are not closed and/or locked.
The sliding doors used in commercial buildings, airports, etc. are typically motor driven, usually by an electric motor. Should the power fail, the sliding doors may be locked in a closed position. To allow egress in the event of a power failure, conventional sliding doors may include a mechanical release assembly which disengages the lock and allows the sliding door to be opened.
Conventional release mechanisms, however, may sometimes be inaccessible to the user. For example, an airport shuttle train traveling between terminals should stop in essentially the same spot in the terminals so that the train doors align with the terminal's sliding doors. The train, however, may stop either before or past the desired spot. In this situation, the release mechanism may be inaccessible.